He had signed on to direct “Creed II,” the sequel to 2015 box-office and critical hit “Creed,” which continued the “Rocky” movie franchise with a new hero in the center of the boxing ring, Michael B. Jordan’s Adonis “Donnie” Creed.

And Caple was taking the reins from director Ryan Coogler, whom he knew from USC’s film school and who not only had earned raves for “Creed” but who then went on to have an all-out smash hit with Marvel Studios’ “Black Panther” early this year.

“Oh, complete pressure, man!” Caple says during a recent stop in his hometown of Cleveland to show and promote the film, which is in theater.

But, he said in the sit-down interview, Coogler and Rocky himself, Sylvester “Sly” Stallone made him feel good about the situation, encouraging him to put his own stamp on the eighth installment in the “Rocky” franchise, a series of films dating to 1976.

“That’s what made me want to do the project,” he adds. “That was my worry: If I tried to do what Ryan did, that’s not me as a filmmaker.”

Before “Creed II,” Caple was best known for writing and directing the 2016 indie drama “The Land,” filmed and set in Cleveland. But, he says, he had reservations about doing “Creed II” because it was a sequel. However, after a meeting with studio executives and Coogler, all parties agreed that Caple at least should meet with Stallone.

Caple tells of being driven by an associate of Stallone’s out to the veteran actor’s mansion, complete with lion statues at the gates and a gigantic front door.

“And he opens this door, and he’s like this tall,” says a seated Caple, his hand at a level putting Stallone at a non-terrifying height. (According to Internet search results, Stallone is in the neighborhood of 5-foot-10.)

Still, to that point, the experience was larger-than-life.

“He has the original Rocky statue as soon as you walk in the house. It’s humongous — it’s crazy. There's only two that exist, and the other’s in (Philadelphia, where the “Rocky” movies primarily are set). I was intimidated, to be honest with you. This is Rocky.”

But soon, he says, it was a relaxing vibe between him and Stallone, a producer of the film.

“When we sat down, he crossed his legs, and it was a cool conversation about character,” Caple says. “He was very much like, ‘What do you think about this guy?’ I saw him be very sensitive about his work, and I was like, ‘Oh, this dude — there’s no ego at the door. He’s not saying, “This is it.” He’s saying, “What do you think?”’ He kept asking that, and I was like, ‘I can work with this — this is a collaboration.’ He didn’t want to mess it up.”

While “Creed II” is from a story by Sasha Penn and Cheo Hodari Coker, the script is credited to Juel Taylor and Stallone, Caple saying the actor synonymous with Rocky writes all the character’s distinct dialogue, which can be a bit loopy. Caple says he would send Stallone a request for a bit of dialogue that conveys an idea.

“He’d send it back, and you’re like, ‘That’s Rocky,’” Caple says.

Specifically, Caple recalls Stallone’s idea for a very minor plot element regarding a street lamp outside Rocky’s home that hasn’t had a working bulb in it for some time, with Rocky complaining about it to Adonis and to the city of Philadelphia.

“He’s like, ‘I could be on the phone with the city talking about this lamp!’” Caple recalls. “And I was like, ‘It could work. It could be cheesy. But every time it happens (in the film), people laugh.”

And then there’s Jordan, who, along with being another producer on the film, carries the acting load as Adonis wins the heavyweight championship belt and then is quickly challenged by Viktor Drago (Florian Munteanu) — son of Dolph Lundgren’s Ivan Drago, who, in “Rocky IV” killed Adonis’ father, Apollo, in the ring and later was defeated by Rocky. Plus, Adonis faces significant changes in his personal life, including the evolution of his relationship with significant other Bianca (Tessa Thompson).

“He works hard — he definitely challenges himself in many ways,” Caple says of Jordan, last seen as strong, determined villain Killmonger in “Black Panther.” “(He has moments in this film) where he’s really vulnerable, and I really wanted to showcase that. I didn’t want to make him, like, super-tough — especially coming off Killmonger — and he was just open to it all.

“He would do anything. If I (suggested) something, he would do it, and that meant a lot. He trusted me.”

When Caple is asked about how he handled going from running the shoot for “The Land” to that of this relatively big-budget studio affair, you get the sense he has gotten this question a lot.

“There’s a misconception on how, like, the set is run differently, you know what I mean? It’s still the same thing. It’s the same thing as a short. You still need craft services. You still need a crew. You still need all these departments for the project,” Caple says. “Ultimately, it’s always about the story, at least with me, so I wasn’t getting caught up in it. I wasn’t making ‘Fast and Furious 8.’”

Fair, but while he notes that he had more people around to assign to tasks that on “The Land” he had to do himself, he acknowledges the shoot for “Creed II” — well more than twice than that of his previous film — was exhausting.

“The days, man — the days are tough. I don’t think people understand: You do it from, like, Monday through Saturday,” he says. “You have one day to recoup, you’re trying to reset, but at the same time you’re already getting ready for Monday. I’m making the shot list, and I’m trying to make it for the whole week. And you’re shooting 12- to 14-hour days, so it was grueling.

“I went vegan on the project so I could stay awake and (not) feel heavy,” he continues. “I did all kinds of things — medicated a lot — just so I could stay focused. I didn’t know it was going to be that crazy.”

Caple says one stamp he tried to put on “Creed II” — a story with echoes to the past and that deals with fathers and sons — is what he calls a vague ghostly presence that pervades the film. You can see this, he points out, in the introduction of Rocky early in the film, almost unnoticed as he has his back to Adonis and is in the distance when he starts speaking to his protege.

“People are, like, ‘Damn, is he dead? Is it a ghost in the room?’ because everything is kind of haunting,” he says. “This film is a little bit darker.”

With “Creed” and this sequel, the “Rocky” franchise has made a fascinating transition, from a story with a white protagonist to one with a black hero — and with two films helmed by black men. While Caple says his film’s themes aren’t really about race — they’re meant to be universal — he’s gotten caught up thinking about what this all means culturally.

“That’s the moment where you’re, like, ‘Man, we’re part of history right now.’”